Method for operating a particle beam apparatus, computer program product and particle beam apparatus for carrying out the method

Abstract

The “rocking beam” method is used to generate a first image of an object and a second image of the object. A control device sets the size and/or the shape of an opening and/or the position of an aperture unit of the particle beam apparatus, and/or at least one electrostatic and/or magnetic deflection unit of the particle beam apparatus for displacing the scanning region, in such a way that a first irradiation direction of the particle beam in the direction of the location on the surface of the object corresponds to a second irradiation direction of the particle beam in the direction of the location on the surface of the object, wherein the first irradiation direction is ascertained from the first image and wherein the second irradiation direction is ascertained from the second image.

1 . A method for operating a particle beam apparatus for processing, imaging and/or analyzing an object, the method comprising:
 generating a particle beam using a beam generator of the particle beam apparatus, the particle beam having charged particles;   selecting at least one value of at least one control parameter for controlling at least one functional unit of the particle beam apparatus using a control device;   controlling the functional unit with the value of the control parameter using the control device of the particle beam apparatus, wherein the particle beam is guided along a first beam path of the particle beam apparatus from the beam generator in the direction of the object;   guiding the particle beam to a location of a scanning region on the surface of the object using a first guide device provided for guiding the particle beam and a second guide device provided for guiding the particle beam, wherein, as viewed from the beam generator in the direction of the object, the first guide device is arranged on and/or in the particle beam apparatus first, followed by the second guide device, wherein the first guide device guides the particle beam away from an optical axis of the particle beam apparatus at a first angle to the optical axis, wherein the second guide device guides the particle beam in a direction of the optical axis at a second angle to the optical axis, wherein, when guiding the particle beam to the location, the first angle runs through a first predeterminable value range and the second angle runs through a second predeterminable value range;   detecting first interaction particles and/or a first interaction radiation using at least one detector, wherein the first interaction particles and/or the first interaction radiation result/results from an interaction of the particle beam with the object when the particle beam is incident on the object;   generating first detection signals using the detected first interaction particles and/or the detected first interaction radiation;   generating a first image of the object using the first detection signals and using the control device;   selecting at least one value of a further control parameter for controlling the functional unit;   controlling the functional unit with the value of the further control parameter using the control device, wherein the particle beam is guided along a second beam path of the particle beam apparatus from the beam generator in the direction of the object;   guiding the particle beam to the location on the surface of the object using the first guide device and the second guide device, wherein the first guide device guides the particle beam away from the optical axis at a third angle to the optical axis, wherein the second guide device guides the particle beam in the direction of the optical axis at a fourth angle to the optical axis, wherein, when guiding the particle beam to the location, the third angle runs through a third predeterminable value range and the fourth angle runs through a fourth predeterminable value range;   detecting second interaction particles and/or a second interaction radiation using the detector, wherein the second interaction particles and/or the second interaction radiation result/results from an interaction of the particle beam with the object when the particle beam is incident on the object;   generating second detection signals using the detected second interaction particles and/or the detected second interaction radiation;   generating a second image of the object using the second detection signals and using the control device; and   setting, using the control device, the size and/or shape of an opening and/or position of an aperture unit of the particle beam apparatus, and/or at least one electrostatic and/or magnetic deflection unit of the particle beam apparatus for displacing the scanning region such that a first irradiation direction of the particle beam in the direction of the location on the surface of the object corresponds to a second irradiation direction of the particle beam in the direction of the location on the surface of the object, wherein the first irradiation direction is ascertained from the first image and wherein the second irradiation direction is ascertained from the second image.   
     
     
         2 . The method according to  claim 1 , wherein the value of the control parameter is a first value and wherein the value of the further control parameter is a second value, the method further comprising:
 using the control parameter as the further control parameter.   
     
     
         3 . The method according to  claim 1 , wherein the first angle is used as the second angle and/or the third angle is used as the fourth angle. 
     
     
         4 . The method according to  claim 1 , wherein the first predeterminable value ranges between 0° and 90°, the second predeterminable value ranges between 0° and 90°, the third predeterminable value ranges between 0° and 90°, the fourth predeterminable value ranges between 0° and 90°, the first predeterminable value range equals the second predeterminable value range, and/or the third predeterminable value range equals the fourth predeterminable value range. 
     
     
         5 . The method according to  claim 1 , wherein the beam generator as is the functional unit in order to set a particle current of the particle beam supplied to the object, the aperture unit as is the functional unit in order to set a convergence angle of the particle beam, a first condenser lens of the particle beam apparatus is the functional unit, and/or a second condenser lens of the particle beam apparatus is the functional unit. 
     
     
         6 . The method according to  claim 1 , wherein backscatter particles are detected as first interaction particles, backscatter particles are detected as second interaction particles, backscattered electrons are detected as first interaction particles, and/or backscattered electrons are detected as second interaction particles. 
     
     
         7 . A non-transitory computer readable medium containing software which is loadable into a processor and which, when executed, causes a particle beam apparatus to perform the following steps:
 generating a particle beam using a beam generator of the particle beam apparatus, the particle beam having charged particles;   selecting at least one value of at least one control parameter for controlling at least one functional unit of the particle beam apparatus using a control device;   controlling the functional unit with the value of the control parameter using the control device of the particle beam apparatus, wherein the particle beam is guided along a first beam path of the particle beam apparatus from the beam generator in the direction of the object;   guiding the particle beam to a location of a scanning region on the surface of the object using a first guide device provided for guiding the particle beam and a second guide device provided for guiding the particle beam, wherein, as viewed from the beam generator in the direction of the object, the first guide device is arranged on and/or in the particle beam apparatus first, followed by the second guide device, wherein the first guide device guides the particle beam away from an optical axis of the particle beam apparatus at a first angle to the optical axis, wherein the second guide device guides the particle beam in a direction of the optical axis at a second angle to the optical axis, wherein, when guiding the particle beam to the location, the first angle runs through a first predeterminable value range and the second angle runs through a second predeterminable value range;   detecting first interaction particles and/or a first interaction radiation using at least one detector, wherein the first interaction particles and/or the first interaction radiation result/results from an interaction of the particle beam with the object when the particle beam is incident on the object;   generating first detection signals using the detected first interaction particles and/or the detected first interaction radiation;   generating a first image of the object using the first detection signals and using the control device;   selecting at least one value of a further control parameter for controlling the functional unit;   controlling the functional unit with the value of the further control parameter using the control device, wherein the particle beam is guided along a second beam path of the particle beam apparatus from the beam generator in the direction of the object;   guiding the particle beam to the location on the surface of the object using the first guide device and the second guide device, wherein the first guide device guides the particle beam away from the optical axis at a third angle to the optical axis, wherein the second guide device guides the particle beam in the direction of the optical axis at a fourth angle to the optical axis, wherein, when guiding the particle beam to the location, the third angle runs through a third predeterminable value range and the fourth angle runs through a fourth predeterminable value range;   detecting second interaction particles and/or a second interaction radiation using the detector, wherein the second interaction particles and/or the second interaction radiation result/results from an interaction of the particle beam with the object when the particle beam is incident on the object;   generating second detection signals using the detected second interaction particles and/or the detected second interaction radiation;   generating a second image of the object using the second detection signals and using the control device; and   setting, using the control device, the size and/or shape of an opening and/or position of an aperture unit of the particle beam apparatus, and/or at least one electrostatic and/or magnetic deflection unit of the particle beam apparatus for displacing the scanning region such that a first irradiation direction of the particle beam in the direction of the location on the surface of the object corresponds to a second irradiation direction of the particle beam in the direction of the location on the surface of the object, wherein the first irradiation direction is ascertained from the first image and wherein the second irradiation direction is ascertained from the second image.   
     
     
         8 . A particle beam apparatus for processing, imaging and/or analyzing an object, comprising:
 at least one beam generator that generates a particle beam with charged particles;   at least one aperture unit for setting the particle beam;   at least one functional unit for generating, setting, guiding and/or shaping the particle beam;   at least one first guide device for guiding the particle beam;   at least one second guide device for guiding the particle beam;   at least one detector for detecting interaction particles and/or interaction radiation which result/results from an interaction of the particle beam with the object when the particle beam is incident on the object;   at least one electrostatic and/or magnetic deflection unit; and   at least one control device having a processor coupled to a non-transitory computer readable medium containing software which is loadable into the processor and which, when executed, causes the particle beam apparatus to perform the following steps:
 generating a particle beam using a beam generator of the particle beam apparatus, the particle beam having charged particles; 
 selecting at least one value of at least one control parameter for controlling at least one functional unit of the particle beam apparatus using a control device; 
 controlling the functional unit with the value of the control parameter using the control device of the particle beam apparatus, wherein the particle beam is guided along a first beam path of the particle beam apparatus from the beam generator in the direction of the object; 
 guiding the particle beam to a location of a scanning region on the surface of the object using a first guide device provided for guiding the particle beam and a second guide device provided for guiding the particle beam, wherein, as viewed from the beam generator in the direction of the object, the first guide device is arranged on and/or in the particle beam apparatus first, followed by the second guide device, wherein the first guide device guides the particle beam away from an optical axis of the particle beam apparatus at a first angle to the optical axis, wherein the second guide device guides the particle beam in a direction of the optical axis at a second angle to the optical axis, wherein, when guiding the particle beam to the location, the first angle runs through a first predeterminable value range and the second angle runs through a second predeterminable value range; 
 detecting first interaction particles and/or a first interaction radiation using at least one detector, wherein the first interaction particles and/or the first interaction radiation result/results from an interaction of the particle beam with the object when the particle beam is incident on the object; 
 generating first detection signals using the detected first interaction particles and/or the detected first interaction radiation; 
 generating a first image of the object using the first detection signals and using the control device; 
 selecting at least one value of a further control parameter for controlling the functional unit; 
 controlling the functional unit with the value of the further control parameter using the control device, wherein the particle beam is guided along a second beam path of the particle beam apparatus from the beam generator in the direction of the object; 
 guiding the particle beam to the location on the surface of the object using the first guide device and the second guide device, wherein the first guide device guides the particle beam away from the optical axis at a third angle to the optical axis, wherein the second guide device guides the particle beam in the direction of the optical axis at a fourth angle to the optical axis, wherein, when guiding the particle beam to the location, the third angle runs through a third predeterminable value range and the fourth angle runs through a fourth predeterminable value range; 
 detecting second interaction particles and/or a second interaction radiation using the detector, wherein the second interaction particles and/or the second interaction radiation result/results from an interaction of the particle beam with the object when the particle beam is incident on the object; 
 generating second detection signals using the detected second interaction particles and/or the detected second interaction radiation; 
 generating a second image of the object using the second detection signals and using the control device; and 
 setting, using the control device, the size and/or shape of an opening and/or position of an aperture unit of the particle beam apparatus, and/or at least one electrostatic and/or magnetic deflection unit of the particle beam apparatus for displacing the scanning region such that a first irradiation direction of the particle beam in the direction of the location on the surface of the object corresponds to a second irradiation direction of the particle beam in the direction of the location on the surface of the object, wherein the first irradiation direction is ascertained from the first image and wherein the second irradiation direction is ascertained from the second image. 
   
     
     
         9 . The particle beam apparatus according to  claim 8 , wherein the particle beam apparatus includes at least one scanning device for raster-scanning the particle beam over the object, and wherein the scanning device comprises includes the first guide device and the second guide device. 
     
     
         10 . The particle beam apparatus according to  claim 8 , wherein the particle beam apparatus comprises includes at least one objective lens that focuses the particle beam on the object. 
     
     
         11 . The particle beam apparatus according to  claim 10 , wherein the beam generator is a first beam generator and the particle beam is a first particle beam with first charged particles, wherein the objective lens is a first objective lens that focuses the first particle beam on the object, the particle beam apparatus further comprising:
 at least one second beam generator that generates a second particle beam with second charged particles; and   at least one second objective lens that focuses the second particle beam on the object.   
     
     
         12 . The particle beam apparatus according to  claim 8 , wherein the electrostatic and/or magnetic deflection unit includes one condenser lens or a plurality of condenser lenses. 
     
     
         13 . The particle beam apparatus according to  claim 8 , wherein the particle beam apparatus is an electron beam apparatus and/or an ion beam apparatus.